Michael Dr. Küchel

8m Class Primary: Figuring, Testing, Handling

The evolution of traditional polishing techniques and a new method developed at Carl Zeiss are reviewed with respect to their suitability to figure large and fast primaries of the 8m class. The role of fast metrology techniques in the figuring process is demonstrated with the ESO NTT primary mirror. The figuring scenario for an 8m mirror as a synthesis of advanced tool technology and fast metrology methods is presented as state of the art at Carl Zeiss. For handling and figuring support of large mirrors new concepts have to be applied. Solutions for the critical steps are outlined.